At present, A X-ray sensor is widely used not only in the medical imaging field but also widely in other technical fields such as metal inspection and so on.
As shown in FIGS. 1 and 2, an array substrate of a current X-ray sensor usually includes a photodiode sensor element 200 and a thin-film transistor element 300 in each pixel region, wherein the photodiode sensor element is primarily intended to receive light and convert an optical signal into an electrical signal by photovoltaic effect, and the thin-film transistor element mainly serves as a control switch and is used to transmit the electrical signal generated by the photovoltaic effect.
The working principle of the current X-ray sensor is as follows: when an X-ray 101 bombards a fluorescent powder 102, visible light generated by the fluorescent powder 102 is incident on the photodiode sensor element 200 of the array substrate and an optical signal is converted into an electrical signal by photovoltaic effect, and the electrical signal is transmitted to a control circuit of the X-ray sensor under control of the thin-film transistor element 300.
Exemplarily, in the prior art, the array substrate of the entire X-ray sensor is manufactured by using nine mask processes which comprises the following steps:
Step 301: forming a gate electrode 11 on a substrate 10 through a first mask process;
Step 302: depositing a gate insulating layer 12 and an active material layer on the substrate formed in the step 301 and forming an active layer 13 on the array substrate through a second mask process;
Step 303: forming a channel blocking layer 14 on the substrate formed in step 302 through a third mask process;
Step 304: depositing an ohmic contact layer 29 on the substrate formed in step 303 and forming a source electrode 15, a drain electrode 16 and a reflective layer 17 through a fourth mask process;
Step 305: forming a semiconductor laminating layer, for example, N-type semiconductor 18, I-type semiconductor 19, P-type semiconductor 20, and a transparent electrode 21 (i.e. a portion of a PIN-type photodiode sensor element) on the substrate formed in step 304 through a fifth mask process;
Step 306: depositing a first passivation layer 22 on the substrate formed in step 305 and forming a first through hole 23 and a second through hole 25 in the first passivation layer 22 through a sixth mask process;
Step 307: forming a light-shielding layer 27, a bias electrode 24 and a signal line 26 on the substrate formed in step 306 through a seventh mask process;
Step 308: depositing a second passivation layer 28 on the substrate formed in step 307 and forming a passivation layer through hole (not shown) in a signal guide region through an eighth mask process; and
Step 309: forming a transparent electrode (not shown) in the signal guide region on the substrate formed in step 308 through a ninth mask process.
During manufacturing an array substrate of an X-ray sensor in the prior art, it is necessary to form a channel blocking layer above the active layer through one mask process, and the array substrate of the X-ray sensor is produced through nine mask processes, which is a complex manufacturing process. Furthermore, the more the number of the mask processes is, the higher the manufacture cost is, and the lower the yield of the product is.